---
description: Genuine Hattori Y121 circuit module, made in Japan. Core control for Y121 movement, drives 3-hand timekeeping, compatible with 377 battery, 6¾×8 ligne.
title: Hattori Y121 Circuit Block Electronic Module - Sofly
image: https://www.soflypart.com/wp-content/uploads/2019/05/Y121C.jpg
---
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- **Hattori Y121 Circuit Block Electronic Module**
[](https://www.soflypart.com/wp-content/uploads/2019/05/Y121C.jpg)
[](https://www.soflypart.com/wp-content/uploads/2019/05/Y121CB.jpg)
# Hattori Y121 Circuit Block Electronic Module
$1.00
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### Discount
| Quantity | Discount (%) | Price |
| --- | --- | --- |
| 1 - 4 | — | $1.00 |
| 5 - 9 | 5% | $0.95 |
| 10+ | 10% | $0.90 |
### Discount
| Quantity | Discount (%) | Price |
| --- | --- | --- |
| 1 - 4 | — | $1.00 |
| 5 - 9 | 5% | $0.95 |
| 10+ | 10% | $0.90 |
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## Product Description
This is a **genuine Hattori Y121 circuit block electronic module**, **made in Japan**, designed for the **Y121 quartz movement**. It serves as the **core control component**, generating the precise 32,768Hz quartz frequency signal to drive the stepper motor for hour, minute, and second hand timekeeping. The Y121 measures **6¾ × 8 ligne (15.30 × 18.20mm)** with a thickness of approximately **2.99mm**, uses a **377 (SR626SW) battery**, with some versions offering up to **4 years** of battery life. This product is **brand new and original**, intended for servicing and repair of Y121 movements.
## Specifications
- **Brand**：Hattori (by Seiko Time Corp./S. Epson)
- **Compatible Movement**：**Y121 / Y121E** quartz movement (including Y121.1, Y121.4 high pinion versions)
- **Part Name**：**Circuit Block Electronic Module**
- **Origin**：**Made in Japan**
- **Quality**：**Genuine original**, brand new
- **Function**：**Generates and processes time signals**, drives stepper motor
## FAQ
**1. Is this circuit module an original Hattori genuine part?**
Yes, **made in Japan**.
**2. Which movements is this circuit module compatible with?**
It fits the **Hattori Y121 series quartz movements** (including Y121.1, Y121.4, Y121E variants). The movement measures **6¾ × 8 ligne** (15.30 × 18.20mm) with **2.99mm** thickness, featuring **hour/minute/seconds hands** and **no date**.
**3. What happens if the circuit module is damaged?**
The circuit module is the **core control component** of the movement, generating the precise quartz oscillation signal and driving the motor. Damage can cause **stoppage or inaccurate timekeeping**. The Y121 offers accuracy of **±20 seconds/month**—circuit failure directly impacts performance. **Timely replacement** is recommended.
## Why Choose SOFLY Watch Parts?
**Fast Worldwide Shipping** – Orders are dispatched within 3 business days.
**Competitive Pricing** – Great value across watch movements, replacement parts and watchmaking tools.
**Extensive Selection** – More than 3,000 watch movements, parts and accessories available.
**Trusted Worldwide** – Trusted by watchmakers, repair professionals and watch enthusiasts worldwide.
**Personalized Sourcing** – Can’t find the part you need? Contact **info@soflypart.com** or WhatsApp **+86 18620212114.**
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It serves as the\u00a0core control component, generating the precise 32,768Hz quartz frequency signal to drive the stepper motor for hour, minute, and second hand timekeeping. The Y121 measures\u00a06\u00be \u00d7 8 ligne (15.30 \u00d7 18.20mm)\u00a0with a thickness of approximately\u00a02.99mm, uses a\u00a0377 (SR626SW) battery, with some versions offering up to\u00a04 years\u00a0of battery life. This product is\u00a0brand new and original, intended for servicing and repair of Y121 movements. Specifications Brand\uff1aHattori (by Seiko Time Corp./S. Epson) Compatible Movement\uff1aY121 / Y121E\u00a0quartz movement (including Y121.1, Y121.4 high pinion versions) Part Name\uff1aCircuit Block Electronic Module Origin\uff1aMade in Japan Quality\uff1aGenuine original, brand new Function\uff1aGenerates and processes time signals, drives stepper motor FAQ 1. Is this circuit module an original Hattori genuine part? Yes,\u00a0made in Japan. 2. 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